The body is made up of many types of cells. Normally, cells grow, divide, and produce more cells when the body needs them. This orderly process helps to keep the body healthy. Sometimes, however, cells keep dividing when new cells are not needed. These extra cells form a mass of tissue, called a growth or tumor. Tumors can be benign or malignant.
A malignant tumor that begins in the ovaries is called ovarian cancer. There are several types of ovarian cancer. Ovarian cancer that begins on the surface of the ovary (epithelial carcinoma) is the most common type. Ovarian cancer that begins in the egg-producing cells (germ cell tumors) and cancer that begins in the supportive tissue surrounding the ovaries (stromal tumors) are rare.
Ovarian cancer cells can break away from the ovary and spread to other tissues and organs in a process called shedding. When ovarian cancer sheds, it tends to seed (form new tumors) on the peritoneum (the large membrane that lines the abdomen) and on the diaphragm. Fluid may collect in the abdomen. This condition is known as ascites. It may make a woman feel bloated, or her abdomen may look swollen.
Ovarian cancer cells can also enter the bloodstream or lymphatic system. Once in the bloodstream or lymphatic system, the cancer cells can travel and form new tumors in other parts of the body.
